The CMOS Inverter 

** Circuit Description **
* dc supplies
Vdd 1 0 DC +5V
* input digital signal
Vi  3 0 DC +5V
* MOSFET inverter circuit
M1 2 3 0 0 MN L=3um W=3um
M2 2 3 1 1 MP L=3um W=9um
* BNR 3um transistor model statements (level 3)
.MODEL MN nmos level=3 vto=.7 kp=4.e-05 gamma=1.1 phi=.6 
+ lambda=.01 rd=40 rs=40  pb=.7 cgso=3.e-10 cgdo=3.e-10
+ cgbo=5.e-10 rsh=25 cj=.00044  mj=.5 cjsw=4.e-10 mjsw=.3
+ js=1.e-05 tox=5.e-08 nsub=1.7e+16  nss=0 nfs=0 tpg=1 xj=6.e-07
+ ld=3.5e-07 uo=775  vmax=100000  theta=.11  eta=.05 kappa=1 
.MODEL MP pmos level=3 vto=-.8 kp=1.2e-05 gamma=.6 phi=.6 
+ lambda=.03 rd=100 rs=100  pb=.6 cgso=2.5e-10 cgdo=2.5e-10
+ cgbo=5.e-10 rsh=80 cj=.00015  mj=.6 cjsw=4.e-10 mjsw=.6
+ js=1.e-05 tox=5.e-08 nsub=5.e+15  nss=0 nfs=0 tpg=1 xj=5.e-07
+ ld=2.5e-07 uo=250  vmax=70000  theta=.13  eta=.3 kappa=1 
** Analysis Requests **
.DC Vi 0 5 50mV
** Output Requests **
* ngspice - save all voltages (allv) + currents (alli)
.save allv alli
.PLOT DC V(2) @m1[id]    $ Figure 13.14 -> .PLOT DC V(2) Id(M1)
.probe
.end